How good is Dell 20" W LCD?

The Dell widescreens are fantastic, although it looks like you're going with the E-series 20" wide model at that price. The FP-series is usually around $350 for the widescreen 20". The main difference is the extra connections (component, composite, s-video) - I use them, so I prefer the FP-series monitors, but for someone who just wants a computer monitor without the extra inputs, the E-series is the best bang for the buck.

I'm on the 2405FPW (previous generation 24" Dell widescreen), and gaming is fine. A very slight ghost is sometimes noticeable in high speed FPS like AA, but perfectly clear in games like WoW, Guildwars, etc. The newer generation is better as far as pixel refresh rates..

Now, some games you WILL want the 4:3 black bars on the sides.. it'll look very distored if you select a 4:3 resolution and play on a widescreen. The good thing is that nearly all games have widescreen resolutions available, and they look great even at non-native resolutions (just keep your desktop and non-games at the native resolution). I frequently played CS:S at 1680x1050 on my native 1920x1200 monitor and it looked fantastic.

For the price, the E-series Dell is a great monitor, and would only suggest the ViewSonic VA1912wb 19" widescreen as an alernative to save some money.